Rotary toothbrush



C. W. RIGGALL, JR

April 19, 1932.

ROTARY TOOTHBRUSH Filed May 28, 1928 gvvuewtot Patented Apr. 19, 1932 PATENT OFFICE CHARLES W. RIGGALL, JR., OF PHILADELPHIA, PENNSYLVANIA ROTARY TOOTHBRUSH Application filed May 28, 1928. Serial No. 281,096.

My invention relates to brushing and polishing, and has for its object the production of an improved tooth brush by means of which the interstices between the teeth may be more effectually cleansed than is possible with the ordinary type of brush in common use.

I attain my object by providing a central stem carrying a series of bristles or the equivalent secured radially to the stem and of such lengths that their outer ends will form figures of revolution whose longitudinal elements 'follow the horizontal contours in general of the molar teeth. The stem is fitted to a coupler of insulating material, which may have a metal core if desired, and around the brush end of the stem I provide a shield of light material such as celluloid, pyralin or the like which fits loosely on the shaft and leaves uncovered only sufficient of the surface I of the brush to properly cover the surface of the teeth. The coupler has a socket formed vin its end, by means of which it can be connected to the shaft end of a small motor, or to a coupling member on the end of a flexible shaft such as is employed by dentists.

Included within the scope of my invention are devices other than a bristle brush for buffing and polishing the teeth and for massaging the gums. The importance of keeping the teeth and gums healthy is becoming so well understood that some people are willing to take the time and the trouble to attain this end. The present invention has for its primary object to assist in this movement, by providing means which in themselves are mechanically correct and which will meet 1 My invention is illustrated in the accompanying drawings, in which Fig. 1 is a longitudinal sectional view of my improved brush, withthe coupler partly in section and a driving motor therefor shown in solid lines.

- Fig. 1a is a detailed view of a modification. Fig. 2 is a transverse section on the line 22 of Fig. 1 looking in the direction of the arrow. In both these figures the teeth engaged by the brush are shown in dotted lines.

Fig. 3 is a side view of the brush detached, with its shield removed.

Fi 4 is a perspective view of the shield detached.

Fig. 5 is a side View with the brush and shield in section, of a modification.

Fig. 6 is an end view of the brush shown in Fig. 5.

Fig. 7 is a side view of a modification of the structure in the preceding figures in which the bristles are replaced by soft rubber or the equivalent for buifing and massaging the gums.

Referring to the drawings, and particularly to Figs. 1 and 3, my brush consists of a bristle body 1, a shaft 2, a coupler 3, which is preferably molded on the shaft, and a guard 4. These may be assembled in several ways, but the one which I prefer at present is as follows: the bristles are molded or otherwise secured into a sleeve 5 which closely fits the shaft 2, with sufiicientfriction to insure the brush turning when the shaft is turned. The sleeve 5 extends slightly beyond the end planes of the bristles to form stops and bearing surfaces for the end plates of the guard 4c. The shaft passes through the opening 7 in the coupler end of the guard (see Fig. 4), but does not eX- tend quite to the outside end, leaving a small portion of the bore of the brush sleeve to receive a stud or nipple 8 on the end of the guard. This centers and holds the outer end of the guard, and yet leaves the brush and the shaft free torotate while the guard remains stationary. The guard 4 and the brush 1 are thus mounted together on the brush shaft, that is, the guard is actually part of the brush assembly resting at one end by means of its stud 8 on the end of the brush sleeve,

rying the bristles and integral with the coupler 3. The guard would then be slotted at the coupler end to fit an annular groove in the coupler, and the outer end would be secured as before. This slotting is rendered necessary by the fact that the shaft cannot be pulled out endwise, and the guard must therefore be slipped onto it by means of a slot. Otherwise the construction is exactly the same as in Figs. 1 and 4. The slot 7a to be used in this modification is shown in Fig. 6 at 4a. Suitable materials for the coupler and brush would be bone, celluloid, hard rubber or composition.

The handle 3 is provided with a socket 9 of proper dimensions to take over the shaft end 10 of the motor 11, with a driving ht. The motor may be of any convenient type and according to my invention its field structure and easing 11a is covered and coated with insulating material such as a hard composition molded and baked upon it, so that the hand of the user does not come in contact with any metal parts. For convenience the operation of the motor may be controlled by a push button or switch 12 mounted in the casing and l have shown a feed wire 13 leading out of a bushed opening 14 to any convenient source of supply.

As an alternative construction, instead of the motor 11, the shaft end 10 may be the coupling end of a flexible shaft similar to those employed by dentists for their machines with suitable driving means therefor.

It is the purpose and design of my invention that where groups of persons are asso ciated together, as for example in a home or family, or a boarding house, or an office, as Well as in a public place like a hotel room, a motor with a driving shaft 10 shall be installed, without any brushes. Any individual possessing a brush with the proper coupling socket 9 may then use the said motor attachment, the brush unit consisting only of the parts shown in Figs. 3 and 4.

Fig. 2 as stated, is a section taken on the line 22 of Fig. 1 looking in the direction of the arrow. In Fig. 1 I have shown in dotted lines the outlines of one side of a set of teeth, comprising five molar teeth, two

incisors and one canine tooth. I have found that it is most important to thoroughly cleanse the molars and especially the interstices between them. As a rule the inner surfacesof all the teeth are kept fairly clean by the tongue, and the front teeth being accessible to both tongue and brush are kept fairly clean, but the molars on both sides are usually neglected.

My brush is shaped to fit the outer surfaces of the molars and to have projecting bristles which during rotation will pass between the same and cleanse the adjacent surfaces, in which cavities usually start. Each segment of the brush has its bristles trimmed so as to form a figure of revolution of which the generating element is a contour of the corresponding tooth. This will be clearly understood from Fig. 2 and the engagement of the bristles with the upper and lower teeth together is shown in Fig. 2. The actual dimensions of the brush, that is to say, the diameter of each segment, the length of each segment and the length of the brush, will necessarily vary for dill'erent persons, but in practice all such variations will probably be referable to not more than 3 or 4 standard sizes, which makes the device strictly columercial.

In cleaning the teeth with this brush, the

upper and lower molars on both sides will first be cleaned on the outside, then the front teeth also on the outside, and finally all the teeth on the inside. Owing to the annular ridges or projecting bristles between the several segments of the brush, it can be applied to the various contours of the inner surfaces of the teeth after a little practice so as to thoroughly cleanse the same. This being so 1 have not found it necessary to make any special provision in the shape of my brush for any but the molar teeth, although it will be umlerstood that if desired a supplemental brush may be provided to lit the front teeth, and a shorter brush or brushes may similarly be provided to fit the inner surfaces of the teeth.

Figs. 5 and (3 show a modification in which the bristles of the brush 1 are secured directly to the shaft 2! which is integral with the coupler 3 and of the same material, which may be celluloid, hard rubber, cellulose composition, or the like. The guard in this case is slotted at 4a or as shown in Fig. (5, to fit into a groove in the coupler, while the outer end of the guard has a stud or nipple on the inside to engage the hollow end of the shaft 2a.

After the teeth are thoroughy cleansed, massage of the gums is recommended. This may be applied to a limited extent by means of the tooth brush itself, but preferably a special head is fitted to the drive shaft, for this purpose. Such a head is shown in Fig. 7 and appears in general the same as the brushhead. Instead of the bristles however, the sleeve 5 in this case carries a soft rubber body 15 and if the instrument is to be used regularly, it carries its ownguard 4 permanently attached to it. This soft rubber massage device is given a concave surface without ridges, as its functions are of course different from those of the brush as such. In the latter the ridges of bristles are relied upon to clear out the interstices between the teeth. The massage head on the other hand has no such function although it may be used to polish the surfaces of the teeth if desired. Its ordinary use is to pass around the gums with its smooth surface rotating rapidly so as to produce stimulation and an increased blood supply.

It should be understood that I am not confined to the specific form, dimensions or materials herein described, as nonessential changes or modifications thereof may be made Without departure from -m invention, and all such changes and modi cations are contemplated by me as within the scope and purview of the appended claims. For example, in case it be desired to reverse the direotion of rotation of my brush, which I have not heretofore described, it is sufficient to attach the brush to the opposite end of the shaft of the motor 11, which is shown at 10a; or, instead of having the motor shaft projecting, have its ends flush With the end surfaces of the motor, and provide them with sockets 88 to receive the end of the shaft '2, as shown in Fig. 1a.

What I claim is: 1. In a rotary driven toothbrush of the type described, a tubular sleeve, bristles mounted on said sleeve, a substantially cylindrical guard adapted to fit over the bristles having an opening in one side to expose the bristles therethrough and having the ends closed, bearing means for the outer end of the brush sleeve inside the outer end of the guard, a bearing opening in the other or inner end of the guard registering with the bore of the brush sleeve and a driving shaft extending through said bearing opening into said brush sleeve the guard being rotatably supported by said brush sleeve and said driving shaft.

2. In a rotary driven toothbrush, the combination described in claim, 1 with the additional element of driving means and a coupler therefor detachably engaging said shaft on the outside of the bearing in the guard,

In testimony whereof I hereunto afix my signature.

CHARLES W. RIGGALL, JR 

